NASA’s Jet Propulsion Laboratory, Pasadena, California
One of the highly desired enhancements to the Mars Exploration Rover (MER) and Phoenix flight missions was the centralized coordinate transform database maintained onboard. Without the database, there are quite a few operations that require cumbersome, error-prone manual calculations on the ground such as pointing a mast camera to an arm tool and driving the rover to the goal defined in a previous site. The Mars Science Laboratory (MSL) Frame Manager flight software implements a centralized frame tree database, which eliminates these cumbersome, error-prone calculations of coordinate entries for commands.

Goddard Space Flight Center, Greenbelt, Maryland
SIVO-PyD gathers and automatically installs (in various computing platforms) a collection of Python-related packages for scientific computing and visualization. All of the packages in distribution are accessible within the Python framework. The distribution is self-contained and can be extended with minimal work.

A number of advantages of modeling fault protection logical design, executing the model, and running a model checker are identified.Model-Based System Engineering is becoming widely adopted at JPL and in industry because model-centric systems introduce improved methods of system engineering. As systems with ever-increasing complexity are developed at JPL, model-centric engineering be comes essential for design, test, and validation. Validation of FP designs is historically problematic, with many examples of inadequate resources (people, time, and budget) and/or unexpected problems. Many factors contribute to these issues, but the problem can be traced to a lack of appreciation of system complexity. When considering a system, there are significantly more ways the system can fail (contingency paths) than ways it can succeed (nominal paths). As NASA continues to develop more complex and capable spacecraft, the behavior state space will increase, stressing the ability of teams to properly understand system behavior.

Molecular flow model is explored as a tool to describe an unusual variety of plume interaction issues.
Goddard Space Flight Center, Greenbelt, Maryland
The analysis and simulation of gases expanding from sources such as rocket nozzles into vacuum, or the effects plumes from these sources create when they interact with solid surfaces, present a considerable challenge to the scientific and engineering communities. As a plume expands into vacuum, density levels, and hence collision rates, decrease rapidly by many orders of magnitude. The main difficulty lies in accurately describing a flow field extending from continuum flow at the nozzle exit, through the transition regime, and reaching free molecule behavior within a relatively short distance downstream. For thrusters, flow at the nozzle exit is usually characterized by high exit velocities and relatively high Mach numbers. Even in regions where significant intermolecular collision rates occur, relative velocity levels are low, and little thermal scattering occurs normal to the mainly radial streamlines. Such observations lead one to consider describing the expansion under certain circumstances using free molecule theory.

NASA’s Jet Propulsion Laboratory, Pasadena, California
The Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) is an Earth imaging radar that flies on a Gulf-Stream Jet. Its mission is to collect data for NASA scientists who are using Synthetic Aperture Radar to develop methods for monitoring changes in the Earth’s surface. As with many other technologies, there is always the possibility of technological or human errors. Since smartphones are mobile, common, and powerful devices, they can be used to reduce the possibility of operator error when the radar is being configured for flight.

Goddard Space Flight Center, Greenbelt, Maryland
The spherical empirical mode decomposition algorithm is an adaptation in the spherical space of the 2D empirical mode decomposition in Euclidian space. This algorithm is a signal analysis method for any spherical data, such as orbital measurements. The two primary advantages of this innovation are the absence of edge effects in the results, and the computational efficiency of the processing.

NASA’s Jet Propulsion Laboratory, Pasadena, California
The NASA Space Telecommunications Radio System (STRS) specification cites a plan for an application repository, similar to an “app store,” but with a wide variety of licensing restrictions on access to different applications, and even different parts of an application package (for instance, wide access to descriptive documentation but limited access to source code). A method is needed to coordinate application artifact storage, license terms, and user access rights.

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